package com.tianji.learning.service.impl;

import com.tianji.common.autoconfigure.mq.RabbitMqHelper;
import com.tianji.common.constants.MqConstants;
import com.tianji.common.exceptions.BizIllegalException;
import com.tianji.common.utils.CollUtils;
import com.tianji.common.utils.UserContext;
import com.tianji.learning.constants.RedisConstants;
import com.tianji.learning.domain.vo.SignResultVO;
import com.tianji.learning.mq.msg.SignInMessage;
import com.tianji.learning.service.ISignRecordService;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.data.redis.connection.BitFieldSubCommands;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;

import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
import java.util.List;

@Slf4j
@Service
@RequiredArgsConstructor
public class SignRecordServiceImpl implements ISignRecordService {

    private final StringRedisTemplate redisTemplate;

    private final RabbitMqHelper mqHelper;

    @Override
    public SignResultVO addSignRecords() {
        // 1. 获取用户id
        Long userId = UserContext.getUser();

        // 2. 拼接key
        LocalDate now = LocalDate.now(); // 当前时间的年月
        String format = now.format(DateTimeFormatter.ofPattern(":yyyyMM"));  // 得到 冒号年月 格式字符串
        String key = RedisConstants.SIGN_RECORD_KEY_PREFIX + userId.toString() + format;

        // 3. 利用bitset命令，将签到记录保存到redis的bitmap中  需要校验是否已签到
        int offset = now.getDayOfMonth() - 1; // 偏移量
        Boolean setBit = redisTemplate.opsForValue().setBit(key, offset, true);  // 返回值是该offset上原来的值
        if(setBit){
            // 说明当天已经签过到
            throw new BizIllegalException("不能重复签到");
        }
        // 4. 计算连续签到的天数
        int days = countSignDays(key, now.getDayOfMonth());
        // 5. 计算连续签到 奖励积分
        int rewordPoints = 0;
        switch (days){
            case 7:
                rewordPoints = 10;
                break;
            case 14 :
                rewordPoints = 20;
                break;
            case 28:
                rewordPoints = 40;
                break;
        }
        // todo  6. 保存积分  发送消息到MQ
        mqHelper.send(MqConstants.Exchange.LEARNING_EXCHANGE,
                MqConstants.Key.SIGN_IN,
                SignInMessage.of(userId, rewordPoints + 1));
        // 7. 封装vo返回
        SignResultVO vo = new SignResultVO();
        vo.setSignDays(days);
        vo.setRewardPoints(rewordPoints);
        return vo;
    }

    /**
     * 计算连续签到多少天
     * @param key 缓存中的key
     * @param dayOfMonth 本月第一天到今天的天数
     * @return
     */
    private int countSignDays(String key, int dayOfMonth) {
        // 1. 求本月第一天到今天所有的签到数据   bitfiled   得到的是十进制
        List<Long> bitField = redisTemplate.opsForValue().bitField(key,
                BitFieldSubCommands.create().get(BitFieldSubCommands.BitFieldType.unsigned(dayOfMonth)).valueAt(0));
        if (CollUtils.isEmpty(bitField)) {
            return 0;
        }
        Long num = bitField.get(0);  // 本月第一天到今天的签到数据 拿到的是十进制
        log.debug("num  {}", num);
        // 2. num转二进制  从后往前推共有多少个1  与运算  右移
        int counter = 0; // 计数器
        while((num & 1) == 1){
            counter ++;
            num = num >>> 1;  // 右移一位
        }
        return counter;
    }
}
